Update columns table adding unused (but SQL Standard) columns
Add domain schema/name (always null) to columns table
Update index/index_columns names to be more consistent with the standard
even though the tables are not standard ones.
Update table constraints and referential constraints to SQL standard.
Update grouping constraints to be consistent

Add a number of columns to routines table to bring it up to SQL standard
too. Several pieces of implied functionality are missing.
Add data type to sequences
Add commit_action (null) to the Tables table